Js calendar month and year issue

When you click on the <a> for a particular day, you execute the dayClicked function to update the calendar. But you don't prevent the default action, which is to navigate to the href, which reloads the page.

You could remove the href, which would prevent the navigation. But this would also affect the style of the link:

$("#days").append("<td class='day_active'><a onclick='dayClicked(" + month + "," + year + ");'>" + i + "</a></td>");

Or, you could add return false; after calling the dayClicked function:

$("#days").append("<td class='day_active'><a href='' onclick='dayClicked(" + month + "," + year + ");return false;'>" + i + "</a></td>");

Or, you could use jQuery delegated events:

function days(month, year) {
    ...
        $("#days").append("<td class='day_active'><a href='' data-month='" + month + "' data-year='" + year + "'>" + i + "</a></td>");
    }
};

$("#days").on("click", ".day_active a", function(evt){
    evt.preventDefault();
    
    var month = this.getAttribute("data-month");
    var year = this.getAttribute("data-year");
    days(month, year);
});